Invasive knotweed in Derry prompts push to stop it

DERRY — The town’s conservation commission is working with the town’s information technology department to identify areas in town infested with Japanese knotweed and other invasive plant species choking roadsides and conservation areas.

Commission member James Arruda said he’s been in touch with IT Director Doug Rathburn about creating a town map highlighting conservation areas, bodies of water and other town-owned areas. The conservation commission could then use that map to pinpoint areas of invasive infestation to control the species and inform residents.

“We would need to go around and identify where the knotweed is and mark the map,” said commission chair Margaret Ives.

Over the past year, the conservation commission has undertaken an aggressive campaign to highlight the prevalence of and problems associated with invasive species, especially the Japanese knotweed.

Arruda said the knotweed is particularly dense along English Range Road, Scobie Pond Road and Island Pond Road.

One major issue associated with knotweed — as opposed to some other species — is that cutting it only causes it to spread.

The commission is looking to work with the town’s public works department on control methods, but Ives and several commission members admitted that the town needs to trim knotweed from some town roadsides in provide proper visibility for drivers.

“I think the commission needs to have a work session with public works about what it is doing with (the invasive species),” said Arruda. He said the town could possibly flag the areas with the knotweed to prevent mowing in those areas.

“Sometimes there is a safety issue and it has to be cut,” Arruda added.

Ives noted that anyone who wants to know what the Japanese knotweed looks like should visit the town’s transfer station.

“If you drive in and look to left and the right, you will see plenty of knotweed,” she said. “We don’t want it and it’s growing abundantly.”

Arruda added that Japanese knotweed is a bitter plant, like rhubarb, and joked that the commission might want to come up with recipes to help get rid of it.